4.2 Quiz Flashcards
What’s unusual about the olfactory receptors?
We continue forming new olfactory neurons throughout our lifetime
Which part of the neuron forms first?
The axon
The 14C concentration in the atmosphere has been declining since 1963. The 14C concentration in neurons of a person’s cerebral cortex and olfactory bulbs corresponds to that of…?
The year of the persons birth
When Sperry cut a newt’s optic nerve and turned the eye upside down, what happened?
Axons of the optic nerve grew back to their original targets
If axons from the retina were prevented from showing spontaneous activity during early development, what would be the probable effect on development of the thalamus?
Axons would not fine-tune their adjustment based on experience, so their connections would be less precise
Why does the spinal cord have the right number of axons to innervate all the muscle cells?
The spinal cord makes an excess of neurons, but those that fail to innervate a muscle die
What is apoptosis?
A programmed mechanism of cell death
Which neurons depend on nerve growth factor to prevent apoptosis in early development?
Neurons in the sympathetic nervous system
At what age does a person have the largest number of neurons?
Before or shortly after birth
If a pregnant woman drinks alcohol, alcohol harms the brain of the fetus not only while it is in the system, but also while it is washing away after drinking. What is the danger while alcohol is washing away?
Overstimulation at glutamate synapses can poison the mitochondria
In the ferret study, what evidence indicated that visual input to the auditory portions of the brain actually produced a visual sensation?
Ferrets that learned to turn one way in response to light in the normal eye turned the same way to light in the rewired eye
An enriched environment promotes growth of axons and dendrites in laboratory rodents. What is known to be one important reason for this effect?
Increased physical activity
If a person is born blind, in what way do the senses of hearing and touch improve?
Through practice the person learns to increase attention to hearing and touch, and those sensations come to activate the occipital cortex
Of the following, which is the strongest evidence to indicate that musical training modifies brain anatomy?
At age 6, children starting musical training did not differ from average, but 15 months later they showed enlargements of several brain areas
Many studies report brain changes after special experiences in adulthood, such as learning to juggle or learning to play golf. Why are some researchers skeptical of these findings?
Most of the reported results were small and have not been replicated
